Diet Tied to Better Breathing in COPD Patients
Study suggests healthy eating might help improve lung function
By Amy Norton
WEDNESDAY, May 21, 2014 (HealthDay News) -- People with certain chronic lung diseases might breathe a bit easier when their diets contain healthy foods like fruits and fish, a new study suggests.
Researchers found that among nearly 2,200 adults with chronic obstructive pulmonary disease (COPD), those who ate fish, grapefruit, bananas and cheese tended to have better lung function and fewer symptoms than their counterparts who did not eat those foods.
COPD is an umbrella term for the progressive lung diseases emphysema and chronic bronchitis. In the United States, about 15 million people have COPD, and the disease is the third leading cause of death nationwide, according to the U.S. Centers for Disease Control and Prevention. Smoking is the leading cause of COPD.
It's not clear yet whether diet has direct effects on COPD patients' lungs. The new study, reported at the American Thoracic Society's annual meeting in San Diego, only shows an association between certain foods and better lung function.
That doesn't prove cause-and-effect, said lead researcher Corrine Hanson, who was scheduled to present the results on Wednesday.
And no one is saying bananas are the magic bullet against COPD, stressed Hanson, an assistant professor at the University of Nebraska Medical Center in Omaha.
But COPD patients who eat fruit, fish and dairy products might have a healthy, well-rounded diet, Hanson said. And it's "plausible," she said, that foods that have antioxidant and anti-inflammatory effects could benefit COPD patients' lungs.
"It's probably the overall dietary pattern that matters," Hanson said.
That, in fact, is what some past research suggests, said Dr. Carlos Camargo, a professor at Harvard Medical School who was not involved in the new study.
In his own research, Camargo has found that people with diets high in fruits, vegetables, fiber-rich grains and fish are less likely to develop COPD compared to people who eat a lot of processed foods, red meat and sweets.
"We think that diet as a whole is important," Camargo said. He added, though, that to really prove that a healthy diet improves lung function, you'd have to do a clinical trial -- where people with COPD would be randomly assigned to follow a particular eating plan or not.
"A trial like that is hard to do," Camargo noted. "But it can be done."
As an example, he cited the recent PREDIMED trial, which showed that the classic Mediterranean diet can cut the odds of heart attack and stroke in high-risk older adults.
"We should do something similar with COPD," Camargo said.
For the current study, Hanson's team used data from a larger project that followed COPD patients over three years. At eight different time points, the participants were asked whether they had eaten grapefruit, bananas, fish or cheese over the past 24 hours.